fix typo in main build (#1130)

Removing problematic backslash which was making the workflow invalid:
https://github.com/aws-observability/aws-otel-java-instrumentation/actions/runs/16834776574/workflow

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under the terms of the Apache 2.0 license.

Author: srprash

.github/workflows/main-build.yml

@@ -277,7 +277,7 @@ jobs:
       - name: Publish main build status
         run: |
           value="${{ needs.build.result == 'success' && needs.e2e-test.result == 'success' && needs.contract-tests.result == 'success' \
-            && needs.application-signals-lambda-layer-build.result == 'success' && \needs.application-signals-e2e-test.result == 'success' && '0.0' || '1.0'}}"
+            && needs.application-signals-lambda-layer-build.result == 'success' && needs.application-signals-e2e-test.result == 'success' && '0.0' || '1.0'}}"
           aws cloudwatch put-metric-data --namespace 'ADOT/GitHubActions' \
             --metric-name Failure \
             --dimensions repository=${{ github.repository }},branch=${{ github.ref_name }},workflow=main_build \